Patent EP-2353766-A2 (EP)
Inventor: DIETRICH SIMON
IPC: B23K11/24
Filed: 2011-01-31
Abstract: The service facility for electric welding device (8), comprises an electrical resistance-spot welding gun, a control- and supply device, a calibration device for the measuring device, and a detection device for the electrical resistance of a welding set (9), where the welding device comprises a measuring device for the welding current. The service facility is formed for the automated operation of the welding device with multiaxial programmable manipulators (11) for handling the workpieces and/or a welding set. The calibration device comprises a measuring device. The service facility for electric welding device (8), comprises an electrical resistance-spot welding gun, a control- and supply device, a calibration device for the measuring device, and a detection device for the electrical resistance of a welding set (9), where the welding device comprises a measuring device for the welding current. The service facility is formed for the automated operation of the welding device with multiaxial programmable manipulators (11) for handling the workpieces and/or a welding set. The calibration device comprises another measuring device for the welding current flowing into the welding set, where the measuring device is connected on a common evaluation device. A common another measuring device is provided with connection- and switching option at different controls and supply facilities. The measuring device is formed in similar manner, where the measuring devices are formed as electrical measuring coils. The another measuring device is formed for the current-conducting contact with electrodes (17) of the welding set, is externally arranged in a working area of the manipulator, and is arranged at the manipulator or at the welding set. The measuring coil is arranged on a bobbin carrier, which comprises a positive electrode recording in the coil inner space. The bobbin carrier is avoidably arranged, and is formed as an electrically conductive plate with both sides of the countersinks. The evaluation device is arranged into the control- and the supply device. The current measurement is simultaneously carried out with the measuring devices and the evaluation, is coupled with the measuring devices to the pulse generation of the stream, and is synchronized with the measuring devices and the pulse generation of the stream. The control- and the supply device comprise a welding control and a welding converter, where the evaluation device is arranged in the welding control system or in a control module of the welding converter. The measuring devices are connected over module to the actual value-processing with the evaluation device of signal-technical manner. The evaluation device determines a correction factor for the work-measuring device and feeds in a current regulator of the control- and the supply device. The measuring devices are arranged on the secondary side of transformer. A voltage tap is arranged at the connection points of the welding set electric circuit and is arranged with the evaluation device, which is captured in constant current of the input voltage and the current intensity and from the current intensity determines/stores the ohmic resistance of the welding set. The evaluation device of the input voltage and the current intensity are repeatedly captured, and forms mean values, where the evaluation device of the measured resistance values stores and performs a trend acquisition, and signalizes extraordinary changes in resistance changes of the welding set. The service facility comprises a detection device for the inductance of the welding set. The control- and the supply device are adjusted to the delivery of a current pulse in closed welding set at an operating point of the workpiece, where the evaluation device of the stream is captured that forms differential di/dt and determines the inductance of the welding set. The control- and the supply device of the inductance values of different operating points (52) are evaluated with a reference store and to the control or the regulation of the welding current in an operation, where the control- and the supply device is formed from the input voltage, the electrical resistance and inductance of the welding set of a detection model for voltage falling on a welded joint and the local electrical resistance actuates the welding set to the change of its closing force. The service facility comprises other devices for processing of electrodes or the caps and/or for the calibration of location references of the welding set.